From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
The fitment of Dunlop low pressure tyres on the first 'SS' chassis.
| Identifier | ExFiles\Box 53\3\ Scan120 | |
| Date | 19th September 1928 | |
| Hs.{Lord Ernest Hives - Chair} 4865 BY/Cgh{W Clough}9/N.19.9.28 With reference to DA{Bernard Day - Chassis Design}/EVL/M.6.9.28 in connection with the proposal to fit 6.75" low pressure tyres on 20" rims in place of 6.75" tyres on 21" rims on the first "SS{S. Smith}" chassis, the Dunlop Company inform us that the dimensions when inflated will be as follows:- Overall diameter 33.75". Width. 6.7". Effective radius 15.5". The Dunlop Co., inform us that they can supply a set of wheels with 20" x 5" rims and 32 x 6.75 balloon tyres to suit in about 7 days time, but we are waiting to hear from W.W. as to what alterations they propose to make to prevent the ends of the cross-steering tube fouling this size of rim. When this matter is settled we will arrange for an order to be placed for one set of wheels and tyres. BY/Cgh.{W Clough} | ||